--- /dev/null
+/*
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License as
+ * published by the Free Software Foundation version 2.
+ *
+ * This program is distributed "as is" WITHOUT ANY WARRANTY of any
+ * kind, whether express or implied; without even the implied warranty
+ * of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ */
+
+#include <linux/module.h>
+#include <linux/platform_device.h>
+#include <linux/regmap.h>
+
+#include <linux/slab.h>
+#include <linux/of.h>
+#include <linux/io.h>
+#include <linux/usb/phy_companion.h>
+#include <linux/clk.h>
+#include <linux/err.h>
+#include <linux/pm_runtime.h>
+#include <linux/delay.h>
+#include <linux/phy/phy.h>
+#include <linux/of_platform.h>
+
+#include <linux/mfd/syscon.h>
+
+/*
+ * TRM has two sets of USB_CTRL registers.. The correct register bits
+ * are in TRM section 24.9.8.2 USB_CTRL Register. The TRM documents the
+ * phy as being SR70LX Synopsys USB 2.0 OTG nanoPHY. It also seems at
+ * least dm816x rev c ignores writes to USB_CTRL register, but the TI
+ * kernel is writing to those so it's possible that later revisions
+ * have worknig USB_CTRL register.
+ *
+ * Also note that At least USB_CTRL register seems to be dm816x specific
+ * according to the TRM. It's possible that USBPHY_CTRL is more generic,
+ * but that would have to be checked against the SR70LX documentation
+ * which does not seem to be publicly available.
+ *
+ * Finally, the phy on dm814x and am335x is different from dm816x.
+ */
+#define DM816X_USB_CTRL_PHYCLKSRC BIT(8) /* 1 = PLL ref clock */
+#define DM816X_USB_CTRL_PHYSLEEP1 BIT(1) /* Enable the first phy */
+#define DM816X_USB_CTRL_PHYSLEEP0 BIT(0) /* Enable the second phy */
+
+#define DM816X_USBPHY_CTRL_TXRISETUNE 1
+#define DM816X_USBPHY_CTRL_TXVREFTUNE 0xc
+#define DM816X_USBPHY_CTRL_TXPREEMTUNE 0x2
+
+struct dm816x_usb_phy {
+ struct regmap *syscon;
+ struct device *dev;
+ unsigned int instance;
+ struct clk *refclk;
+ struct usb_phy phy;
+ unsigned int usb_ctrl; /* Shared between phy0 and phy1 */
+ unsigned int usbphy_ctrl;
+};
+
+static int dm816x_usb_phy_set_host(struct usb_otg *otg, struct usb_bus *host)
+{
+ otg->host = host;
+ if (!host)
+ otg->state = OTG_STATE_UNDEFINED;
+
+ return 0;
+}
+
+static int dm816x_usb_phy_set_peripheral(struct usb_otg *otg,
+ struct usb_gadget *gadget)
+{
+ otg->gadget = gadget;
+ if (!gadget)
+ otg->state = OTG_STATE_UNDEFINED;
+
+ return 0;
+}
+
+static int dm816x_usb_phy_init(struct phy *x)
+{
+ struct dm816x_usb_phy *phy = phy_get_drvdata(x);
+ unsigned int val;
+ int error;
+
+ if (clk_get_rate(phy->refclk) != 24000000)
+ dev_warn(phy->dev, "nonstandard phy refclk\n");
+
+ /* Set PLL ref clock and put phys to sleep */
+ error = regmap_update_bits(phy->syscon, phy->usb_ctrl,
+ DM816X_USB_CTRL_PHYCLKSRC |
+ DM816X_USB_CTRL_PHYSLEEP1 |
+ DM816X_USB_CTRL_PHYSLEEP0,
+ 0);
+ regmap_read(phy->syscon, phy->usb_ctrl, &val);
+ if ((val & 3) != 0)
+ dev_info(phy->dev,
+ "Working dm816x USB_CTRL! (0x%08x)\n",
+ val);
+
+ /*
+ * TI kernel sets these values for "symmetrical eye diagram and
+ * better signal quality" so let's assume somebody checked the
+ * values with a scope and set them here too.
+ */
+ regmap_read(phy->syscon, phy->usbphy_ctrl, &val);
+ val |= DM816X_USBPHY_CTRL_TXRISETUNE |
+ DM816X_USBPHY_CTRL_TXVREFTUNE |
+ DM816X_USBPHY_CTRL_TXPREEMTUNE;
+ regmap_write(phy->syscon, phy->usbphy_ctrl, val);
+
+ return 0;
+}
+
+static struct phy_ops ops = {
+ .init = dm816x_usb_phy_init,
+ .owner = THIS_MODULE,
+};
+
+static int dm816x_usb_phy_runtime_suspend(struct device *dev)
+{
+ struct dm816x_usb_phy *phy = dev_get_drvdata(dev);
+ unsigned int mask, val;
+ int error = 0;
+
+ mask = BIT(phy->instance);
+ val = ~BIT(phy->instance);
+ error = regmap_update_bits(phy->syscon, phy->usb_ctrl,
+ mask, val);
+ if (error)
+ dev_err(phy->dev, "phy%i failed to power off\n",
+ phy->instance);
+ clk_disable(phy->refclk);
+
+ return 0;
+}
+
+static int dm816x_usb_phy_runtime_resume(struct device *dev)
+{
+ struct dm816x_usb_phy *phy = dev_get_drvdata(dev);
+ unsigned int mask, val;
+ int error;
+
+ error = clk_enable(phy->refclk);
+ if (error)
+ return error;
+
+ /*
+ * Note that at least dm816x rev c does not seem to do
+ * anything with the USB_CTRL register. But let's follow
+ * what the TI tree is doing in case later revisions use
+ * USB_CTRL.
+ */
+ mask = BIT(phy->instance);
+ val = BIT(phy->instance);
+ error = regmap_update_bits(phy->syscon, phy->usb_ctrl,
+ mask, val);
+ if (error) {
+ dev_err(phy->dev, "phy%i failed to power on\n",
+ phy->instance);
+ clk_disable(phy->refclk);
+ return error;
+ }
+
+ return 0;
+}
+
+static UNIVERSAL_DEV_PM_OPS(dm816x_usb_phy_pm_ops,
+ dm816x_usb_phy_runtime_suspend,
+ dm816x_usb_phy_runtime_resume,
+ NULL);
+
+#ifdef CONFIG_OF
+static const struct of_device_id dm816x_usb_phy_id_table[] = {
+ {
+ .compatible = "ti,dm8168-usb-phy",
+ },
+ {},
+};
+MODULE_DEVICE_TABLE(of, dm816x_usb_phy_id_table);
+#endif
+
+static int dm816x_usb_phy_probe(struct platform_device *pdev)
+{
+ struct dm816x_usb_phy *phy;
+ struct resource *res;
+ struct phy *generic_phy;
+ struct phy_provider *phy_provider;
+ struct usb_otg *otg;
+ const struct of_device_id *of_id;
+ const struct usb_phy_data *phy_data;
+ int error;
+
+ of_id = of_match_device(of_match_ptr(dm816x_usb_phy_id_table),
+ &pdev->dev);
+ if (!of_id)
+ return -EINVAL;
+
+ phy = devm_kzalloc(&pdev->dev, sizeof(*phy), GFP_KERNEL);
+ if (!phy)
+ return -ENOMEM;
+
+ res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+ if (!res)
+ return -ENOENT;
+
+ phy->syscon = syscon_regmap_lookup_by_phandle(pdev->dev.of_node,
+ "syscon");
+ if (IS_ERR(phy->syscon))
+ return PTR_ERR(phy->syscon);
+
+ /*
+ * According to sprs614e.pdf, the first usb_ctrl is shared and
+ * the second instance for usb_ctrl is reserved.. Also the
+ * register bits are different from earlier TRMs.
+ */
+ phy->usb_ctrl = 0x20;
+ phy->usbphy_ctrl = (res->start & 0xff) + 4;
+ if (phy->usbphy_ctrl == 0x2c)
+ phy->instance = 1;
+
+ phy_data = of_id->data;
+
+ otg = devm_kzalloc(&pdev->dev, sizeof(*otg), GFP_KERNEL);
+ if (!otg)
+ return -ENOMEM;
+
+ phy->dev = &pdev->dev;
+ phy->phy.dev = phy->dev;
+ phy->phy.label = "dm8168_usb_phy";
+ phy->phy.otg = otg;
+ phy->phy.type = USB_PHY_TYPE_USB2;
+ otg->set_host = dm816x_usb_phy_set_host;
+ otg->set_peripheral = dm816x_usb_phy_set_peripheral;
+ otg->usb_phy = &phy->phy;
+
+ platform_set_drvdata(pdev, phy);
+
+ phy->refclk = devm_clk_get(phy->dev, "refclk");
+ if (IS_ERR(phy->refclk))
+ return PTR_ERR(phy->refclk);
+ error = clk_prepare(phy->refclk);
+ if (error)
+ return error;
+
+ pm_runtime_enable(phy->dev);
+ generic_phy = devm_phy_create(phy->dev, NULL, &ops);
+ if (IS_ERR(generic_phy))
+ return PTR_ERR(generic_phy);
+
+ phy_set_drvdata(generic_phy, phy);
+
+ phy_provider = devm_of_phy_provider_register(phy->dev,
+ of_phy_simple_xlate);
+ if (IS_ERR(phy_provider))
+ return PTR_ERR(phy_provider);
+
+ usb_add_phy_dev(&phy->phy);
+
+ return 0;
+}
+
+static int dm816x_usb_phy_remove(struct platform_device *pdev)
+{
+ struct dm816x_usb_phy *phy = platform_get_drvdata(pdev);
+
+ usb_remove_phy(&phy->phy);
+ pm_runtime_disable(phy->dev);
+ clk_unprepare(phy->refclk);
+
+ return 0;
+}
+
+static struct platform_driver dm816x_usb_phy_driver = {
+ .probe = dm816x_usb_phy_probe,
+ .remove = dm816x_usb_phy_remove,
+ .driver = {
+ .name = "dm816x-usb-phy",
+ .pm = &dm816x_usb_phy_pm_ops,
+ .of_match_table = of_match_ptr(dm816x_usb_phy_id_table),
+ },
+};
+
+module_platform_driver(dm816x_usb_phy_driver);
+
+MODULE_ALIAS("platform:dm816x_usb");
+MODULE_AUTHOR("Tony Lindgren <tony@atomide.com>");
+MODULE_DESCRIPTION("dm816x usb phy driver");
+MODULE_LICENSE("GPL v2");
Code Review / kvmfornfv.git / blobdiff